3822_03 Datasheet, PDF (265/328 Pages) Renesas Technology Corp – 8-BIT SINGLE-CHIP MICROCOMPUTER

APPLICATION
2.10 Oscillation circuit
(2) Clock output function
The internal clock φ can be output from the φ pin by setting the φ output control bit (bit 0) of the φ
output control register (address 002A16) to “1.”
The φ pin is also used as port P41. Accordingly, to use it as an φ pin, set bit 1 of the port P4 direction
register to “1.”
Figure 2.10.4 shows the structure of the φ output control register.
φ output control register
b7 b6 b5 b4 b3 b2 b1 b0
φ output control register (CKOUT) [Address 2A 16]
B
Name
0 ^{φ output control bit}
Functions
At reset R W
0: Port function
0
1: φ clock output
(Port direction register
= “1”)
1 _{Nothing is allocated. These bits cannot be}
to _{written to and are fixed to “0” at reading.}
7
0 0×
Fig. 2.10.4 Structure of φ output control register
3822 GROUP USER’S MANUAL
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